Congress has supported NASA's Exploration Systems program for years. We have expressed this support in law and with funding, from one administration to the next.

After all these years, after billions of dollars spent, we are facing more delays and cost overruns. Recent hurricanes and tornadoes have damaged some facilities and slowed localized progress but many of the problems are self-inflicted.

It is very disappointing to hear about delays caused by poor execution when the U.S. taxpayer has invested so much in these programs.

For the last eight years, Congress has defended the Space Launch System and Orion Crew Vehicle from attempts at cancellation and proposed budget cuts. Funding for the Exploration Systems Development now is nearly $4 billion a year.

The Government Accountability Office reported last spring that the first launch of the SLS likely will be delayed a year from late 2018 to late 2019. Delays with the delivery of the European Service Module could push this into 2020.

If this is the case, the schedule for the first launch with crew is also at risk because of the time needed to upgrade the mobile launch platform.

The NASA Inspector General reported this week that the development of Exploration Systems is one of the most significant challenges facing NASA. The IG highlighted problems facing all facets of the program: SLS, Orion and the ground systems.

NASA and the contractors should not assume future delays and cost overruns will have no consequences. If delays continue, if costs rise and if foreseeable technical challenges arise, no one should assume the U.S. taxpayers or their representatives will tolerate this.

Alternatives to SLS and Orion almost certainly would involve significant taxpayer funding and lead to further delays. But the more setbacks SLS and Orion face, the more support builds for other options.

Other space exploration programs at NASA, like the so-called Commercial Crew Program also are facing significant delays and challenges.

NASA has suffered for decades from program cancellations that have delayed exploration goals.

As NASA's exploration systems progress from development to production, operations and maintenance, NASA and its contractors must bring down costs and guarantee deliveries on time.

To this end, I was glad to see NASA issue a request for information last November in order to explore ways to reduce costs.

Moving to firm fixed-price contracts for production might be an appropriate path going forward but only if it benefits the taxpayer.

Congress needs to have confidence in NASA and the exploration systems contractors, which I don't believe we have now. That confidence is ebbing. If it slips much further, NASA and the contractors will have a hard time regaining their credibility.